Comparison of oral antibiotic failure rates in post-Roux-en-Y gastric bypass patients versus controls

Background: Due to the malabsorptive nature of the Roux-en-Y gastric bypass (RYGB), there is a potential for impaired absorption of oral medications. Clinical outcomes of patients who receive oral antibiotics after RYGB have not been adequately described in the literature.

Objectives: The primary objective was composite therapeutic failure. Secondary objectives included comparing failure rates between antibiotic classes and at various time points since RYGB.

Setting: University hospital, United States.

Methods: Patients with a history of RYGB and controls who received an eligible oral antibiotic for urinary tract infection, skin and soft tissue infection, or community acquired pneumonia between April 1, 2008, and September 30, 2015, were included via retrospective chart review. Therapeutic failure rates between groups were compared and adjusted for body mass index and infection type. Failure rates among antibiotic classes and various time points since RYGB (0-1 yr, 1-1.9 yr, and≥2 yr) were also compared.

Results: A total of 58 RYGB and 128 controls met inclusion and exclusion criteria. Composite therapeutic failure occurred in the RYGB and control group in 14 (24.1%) and 20 patients (15.6%), respectively (P = .18; odds ratio, 1.8; 95% confidence interval .8-4.4). RYGB patients who received fluoroquinolones or sulfonamides had a significantly increased risk of therapeutic failure.

Conclusions: RYGB was not associated with a statistically significant increased risk of composite therapeutic failure of oral antibiotics in the treatment of urinary tract infection, skin and soft tissue infection, or community acquired pneumonia compared with patients with no history of gastrointestinal resection. Further research is warranted to understand clinical outcomes of RYGB patients who receive oral antibiotics.